https://dagster.io/ logo
#ask-ai
Title
# ask-ai
j

Jerry Bao

02/28/2024, 9:46 PM
How can I setup Dagster to alert whenever an asset fails to materialize?
s

Scout

02/28/2024, 9:46 PM
To set up alerts in Dagster for when an asset fails to materialize, you can follow these steps: 1. Sign in to your Dagster Cloud account. 2. In the top navigation, click Deployment. 3. Click the Alerts tab. 4. Click + Create alert policy. 5. From the Alert Policy type drop-down, select the type of alert to create. 6. In the Create alert policy window, fill in the following: - Alert policy name - Enter a name for the alert policy. For example,
slack_urgent_failure
. - Description - Enter a description for the alert policy. For asset-based alerts, fill out these additional options: - Asset group - Select the asset group to monitor. You will have the option to select from all asset groups in the deployment. - Asset key - Select the asset key to monitor. You will have the option to select from all asset keys in the deployment. Note: If you select an asset group, you will not be able to select an asset key. - Events - Select whether the alert should trigger on asset materialization failure, asset materialization success, asset check error, asset check warn, asset check passed, or asset check failure to execute. Finally, select the Notification service you wish to use, such as Slack, and configure it accordingly. Remember that alert policies are configured on a per-deployment basis, so asset alerts configured in a
prod
deployment are only applicable to assets in that deployment. Currently, Slack and email notifications are supported. Please note that asset-based alert policies are still experimental and may be subject to change as we gather user feedback. Additionally, Organization Admin, Admin, or Editor permissions are required to manage alerts in Dagster Cloud. If you're a Dagster Cloud Admin or Editor, you can only manage alerts in deployments where you're an Admin.
j

Jerry Bao

02/28/2024, 9:47 PM
@Scout How can I set it up to send an event to Datadog? I dont use dagster cloud
s

Scout

02/28/2024, 9:47 PM
As of my knowledge cutoff date in early 2023, Dagster does not provide a built-in integration specifically for sending alerts directly to Datadog. However, you can set up custom logic within your Dagster instance to send events to Datadog when an asset fails to materialize. Here's a general approach you can take to send events to Datadog: 1. Datadog API: Familiarize yourself with the Datadog API, particularly the Events API, which allows you to post events to your Datadog event stream. 2. Datadog Client: Use the
datadog
Python package, which provides a Python client for interacting with the Datadog API. You can install it using `pip`:
Copy code
shell
   pip install datadog
3. Dagster Resources: Create a custom Dagster resource that encapsulates the logic for sending events to Datadog. This resource will use the Datadog client to send events. 4. Asset Observers: Implement asset observers in your Dagster repository. Asset observers are hooks that allow you to perform custom logic when an asset is materialized or when materialization fails. 5. Send Events on Failure: Within the asset observer, check for materialization failure events and use the Datadog resource to send an event to Datadog when a failure occurs. Here's a simplified example of how you might set up a custom resource and asset observer to send events to Datadog:
Copy code
python
from dagster import resource, AssetMaterialization, AssetKey, EventRecordsFilter
from datadog import initialize, api

# Initialize the Datadog client
options = {
    'api_key': 'your_api_key',
    'app_key': 'your_app_key'
}
initialize(**options)

@resource
def datadog_resource(_):
    def post_event(title, text, tags):
        api.Event.create(title=title, text=text, tags=tags)
    return post_event

@asset_observer(required_resource_keys={"datadog"})
def datadog_asset_observer(context, event):
    if isinstance(event, AssetMaterialization) and not event.materialization_success:
        asset_key = event.asset_key
        # Construct a title and message for the Datadog event
        title = f"Asset Materialization Failure: {asset_key}"
        text = f"An asset with key {asset_key} failed to materialize."
        tags = ['dagster', f'asset:{asset_key}']
        # Send the event to Datadog
        context.resources.datadog.post_event(title, text, tags)

# In your repository definition, include the resource and observer
@repository
def my_repository():
    return [
        ...,
        datadog_asset_observer,
        datadog_resource,
        ...
    ]
Please note that this is a high-level example and you would need to adapt it to your specific use case and environment. Additionally, you should handle authentication and error checking appropriately. Remember to replace `'your_api_key
'` and
'your_app_key'
with your actual Datadog API and application keys. You should also ensure that the Datadog client is properly configured to communicate with the Datadog API from your environment. Keep in mind that the actual implementation details may vary based on the version of Dagster you are using and any updates to the Dagster or Datadog APIs that have occurred after my knowledge cutoff date. Always refer to the latest documentation for both Dagster and Datadog for the most up-to-date guidance.
j

Jerry Bao

02/28/2024, 9:53 PM
@Scout
@asset_observer
is not a decorator that exists in the API
s

Scout

02/28/2024, 9:53 PM
I apologize for the confusion. You are correct that
@asset_observer
is not a decorator in the Dagster API. Instead, you can use Dagster's event hooks to respond to asset events. Here's how you can set up a Dagster event hook to send an alert to Datadog when an asset fails to materialize: 1. Create a Hook: Define a custom event hook using the
@event_hook
decorator. This hook will be triggered after the execution of an op. 2. Check for Asset Materialization Events: Within the hook, check the event log for
AssetMaterialization
events and determine if there was a failure. 3. Send an Event to Datadog: If there was a failure, use the Datadog API to send an event. Here's an example of how you might implement this:
Copy code
python from dagster import event_hook, HookContext from datadog import initialize, api  # Initialize the Datadog client options = {     'api_key': 'your_api_key',     'app_key': 'your_app_key' } initialize(**options)  def send_datadog_event(title, text, tags):     api.Event.create(title=title, text=text, tags=tags)  @event_hook(required_resource_keys={"datadog"}) def datadog_event_hook(context: HookContext):     for event_record in context.event_log_entry.dagster_event.event_specific_data.materialization_events:         if not event_record.materialization_success:             asset_key = event_record.asset_key.to_string()             title = f"Asset Materialization Failure: {asset_key}"             text = f"An asset with key {asset_key} failed to materialize."             tags = ['dagster', f'asset:{asset_key}']             send_datadog_event(title, text, tags)  # In your job definition, include the hook @job(hooks={datadog_event_hook}) def my_job():     my_op()
In this example,
my_op
would be an op that you expect to materialize an asset. The
datadog_event_hook
is attached to the job and will be triggered after
my_op
executes. If the asset fails to materialize, the hook will send an event to Datadog. Please ensure that you have the
datadog
Python package installed and that you replace
'your_api_key'
and
'your_app_key'
with your actual Datadog API and application keys. Keep in mind that this example is a simplified illustration and you may need to adapt it to fit the specifics of your Dagster setup and the structure of your assets and ops. Always refer to the latest Dagster documentation for the most current patterns and practices for implementing hooks and handling events.
j

Jerry Bao

02/28/2024, 9:55 PM
@Scout
@event_hook
is also not a decorator
s

Scout

02/28/2024, 9:55 PM
I apologize for the oversight. You are correct that
@event_hook
is not a decorator in the Dagster API. Instead, Dagster provides hooks that can be triggered on op success or failure. To send an alert to Datadog when an asset fails to materialize, you can use a
@failure_hook
. Here's an example of how you might set up a failure hook to send an alert to Datadog:
Copy code
python from dagster import failure_hook, HookContext from datadog import initialize, api  # Initialize the Datadog client options = {     'api_key': 'your_api_key',     'app_key': 'your_app_key' } initialize(**options)  def send_datadog_event(title, text, tags):     api.Event.create(title=title, text=text, tags=tags)  @failure_hook(required_resource_keys={"datadog"}) def datadog_failure_hook(context: HookContext):     # You can access the op name and error information from the context     op_name = context.op.name     error_info = context.op_exception      title = f"Failure in op: {op_name}"     text = f"An error occurred in op {op_name}: {error_info}"     tags = ['dagster', f'op:{op_name}']      send_datadog_event(title, text, tags)  # In your job definition, include the hook @job(hooks={datadog_failure_hook}) def my_job():     my_op()
In this example,
my_op
would be an op that you expect to materialize an asset. The
datadog_failure_hook
is attached to the job and will be triggered if
my_op
fails. If the op fails, the hook will send an event to Datadog. Please ensure that you have the
datadog
Python package installed and that you replace
'your_api_key'
and
'your_app_key'
with your actual Datadog API and application keys. Keep in mind that this example is a simplified illustration and you may need to adapt it to fit the specifics of your Dagster setup and the structure of your assets and ops. Always refer to the latest Dagster documentation for the most current patterns and practices for implementing hooks and handling events.
j

Jerry Bao

02/28/2024, 9:57 PM
@Scout do op hooks work for assets as well?
s

Scout

02/28/2024, 9:57 PM
As of the latest information available to me, op hooks in Dagster are designed to be used with ops within jobs or graphs. They are not directly applicable to software-defined assets. This is because assets in Dagster have a different lifecycle and set of abstractions compared to ops. However, there has been community interest in enabling hooks for software-defined assets, as indicated by discussions and feature requests on the Dagster GitHub repository. As of now, if you want to trigger alerts or perform actions when an asset fails to materialize, you would typically handle this within the asset computation itself or by using the facilities provided by the asset's materialization process. If you are using assets and want to perform actions similar to hooks, you might consider the following approaches: 1. Asset Sensors: Use asset sensors to monitor asset materializations and trigger alerts or actions based on changes in asset states. 2. Custom Logic in Asset Computations: Include custom logic within your asset computation function to send alerts or notifications when exceptions occur or certain conditions are met. 3. Graph-backed Assets: If you are using graph-backed assets, you can apply op hooks to the ops within the graph, and these hooks will be triggered as part of the asset computation. It's important to keep an eye on the Dagster changelog and documentation for any updates regarding this functionality, as the Dagster team may introduce new features or patterns that could change the way hooks and assets interact.
8 Views